A method and a device for controlled shutdown and restart of an internal combustion engine are described in WO 01/48373 A1 in which the engine is actively or passively positioned at a predetermined crank angle at rest. The position is stored and later available at restart. The predetermined angle is then used to initiate cylinder-specific fuel injection and ignition.
Typically, an internal combustion engine is started by a starter motor, which brings the crankshaft to a minimum rotational speed. The motoring torque to rotate the engine varies as a function of crank angle due largely to the compression and expansion of air in the cylinders. The peaks in the motoring torque are overcome by the torque delivered by the starter and the inertial energy stored in the rotating components, namely the starter and engine.
The motoring torque increase as the temperature decreases. Thus, a starter with enough low-speed torque to overcome the motoring torque peaks at low temperature is desired. At warmer temperatures, a smaller electric motor would be sufficient. However, a larger motor is needed to cover the range of operating temperatures.